A prior art device and a wheel equipped therewith are known from EP 0 751 017 B1. The known device has a housing of a dimensionally stable plastic with an approximately cuboid base part and a centrally arranged extension, in which a cavity of calotte-like shape is formed, in which an elongated hole is situated. A tire valve has at its internally located end (subsequently designated as valve base) a calotte-shaped bulge, which fits into the calotte-shaped cavity, and a threaded bore, which continues into the valve bore necessary for filling the tire with compressed air. A hollow screw can be turned into the threaded bore through the elongated hole in the extension of the housing, by which hollow screw the housing is fastened to the valve base. By means of the elongated hole, the housing can be adjusted after the mounting of the valve on the wheel such that the housing rests on the rim well by its side facing the rim well of the wheel. To achieve that the housing receives a stable position of rest on the rim, two feet are provided on the two side parts of the housing remote from the valve, with the greatest possible distance from the valve base, which feet rest on the rim well. Together with the fastening of the housing on the valve base, thereby a statically clearly determined 3-point bearing is produced for the housing.
In the housing there are accommodated a pressure measuring device, a transmitting device for the transmission of the pressure measurement values by radio to a receiver provided in the vehicle, a control device and a battery for the electric power supply of the device. These components of the device are embedded into a casting compound, with which the shell-shaped housing is filled to the brim, with the feet of the housing, however, remaining free.
On mounting of a tire onto the rim and on removing a tire from the rim, it can occur that the device for measuring the air pressure is damaged. In such a case, the device must be completely replaced.
It is an object of the present invention to show a way where the risk of damage to the device for measuring the air pressure can be reduced, without substantially increasing the weight of the device.